Variations in Plasma IL-2 and IL-10 in Relationship with Plasmodium Parasite Density

Study Background: Plasma IL-2 and IL-10 are cytokines for immuno regulation and immuno modulation in infectious diseases. IL10 inhibit synthesis of IFN gamma, IL-2, IL-3, TNF. Plasmodium infection is associated with reproduction of cytokines for innate and acquired immunity.
Aim and Objective: This work was designed to determine variations in plasma IL-2 and IL-10 in relationship with plasmodium parasite density.

Materials and Methods: Out of one hundred and sixteen (116) initially recruited only fifty Plasmodium infected female and male (female =25; male =25) aged 4-70 years free of M. tuberculosis and seronegative to HBsAg, HCV and HIV were recruited for the work.. Fifty age matched Plasmodium non-infected subjects were studied as control (female =25; male =25). Only subjects who were free of M. tuberculosis and seronegative to HIV, HCV, HBsAg test and AFB negative were recruited for the work. Plasma IL-2, IL-10, HIV, HBsAg and HCV were determined in the patients and the control subject immunochemically by ELISA while Identification of Plasmodium spp was determined in the blood of the patients and the control subject using WHO standard technique for the laboratory diagnosis of plasmodium infection in malaria endemic area.

Results: A frequency of : 12.0%(14) Anti-HCV seropositive, 6.9%(8) Anti-HIV seropositive, 19.8%(23) HBsAg seropositive, 13.8% (16) AFB positive patients and 4.3%(5) indeterminate results was obtained from the 116 Plasmodium infected patients initially recruited. There was a significantly Higher plasma value of IL-10 in plasmodium infected patients with parasite density of 500-999 and ≥1000 than the control subjects with p<0.05. There was also a significantly lower mean plasma value of IL-10 in plasmodium infected patients with parasite density of 50-499 than those patients with parasite density 500-999 and ≥1000 with p<0.05.

Conclusion: Plasmodium parasitemia and increase in parasite density has been found to significantly increase the plasma value of IL-10 with no significant change in the plasma value of IL-2. There was also an evidence of HIV, HCV, HBV and M. tuberculosis co-infection with Plasmodium spp .